Rotary engine.



PATENTBD' MAY 15, 1906.

H. E. THOMAS. ROTARY ENGINE. APPLIoATlvoN FILED AUG. 28, 1905v 2 SHEETS-SHEET 1 Ilm . au. j t\ /A/vE/v roi? mm/w @am M714# mA/1 wt No. 820,447. `J PATBNTBD MAY 15, 190s.

H. B. THOMAS.

ROTARY ENGINE.

PPLI TI N A UA 0 FILED AUG 28, 1905 2 SEBBTS SHEBT 2l UNITED STATES PATENT OFFICE.

HENRY E. THOMAS, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR OF ONE- HALF TO GEORGE TRESSLER, OF SAN FRANCISCO, CALIFORNIA.

,'BOTARY ENGlNE.

Speccation of Letters Patent.

A.f atenteci May 15, 1906.

To all whom it may concern.-

Be it knovn that I, HENRY E. THOMAS, a citizen of the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements in Rotary Engines, of which the following is a specification.

This invention relates to rotary engines adapted to be operated by steam, compressed air, water, gasolene, or any other fluid.

The object of the invention is to provide an engine of this character which shall be simple in construction, contain few movable parts, which will work economically as re gards the consum tion of steam or other fluid, which can e easily operated, and which can readily be reversed, being adapted to be driven equally well in either direction.

In the accompanying drawings, Figure 1 is a transverse section of the engine. Fig. 2 is a front view, the casing being removed. Fig. 3 is a side view. Fig. 4 is a section on the line A 4 of Fig. 2.

Referring to the drawings, 1 indicates a casing having a suitable base 2 and closed at the end by heads 3, bolted to the flanges 4. In suitable hubs or bearings 5 in said head is mounted a main driving-shaft 6, carrying at -one end a belt-pulley 7 and at the other end Aa gear-wheel 8, the latter meshing with a gear-wheel 9 upon a shaft 10, revolving in the upper portion of the casing and being journaled in hubs or bearings 11, formed in the heads. The object of employing the two gear-wheels so meshing with each other is to insure that the shafts and the cylinders carried thereon rotate in unison. v

Upon the main shaft 6 is secured a drum 13, having the radial ribs 14 and carrying on its periphery the vanes or pistons 15. Upon the other shaft is also secured a similar drum 16, and in the periphery of the latter drum are formed grooves 17, which are substantially V-shaped in cross-section, corresponding with the cross-sectional form of the vanes, the vanes, however, being narrower or tapering more sharply than the grooves. The two drums revolve in close contact with each other in the plane throu h the shafts, this close contact forming a closure for the steam, preventing backward escape thereof, and the outer edges of these vanes 15 travel in close contact with the inner surface of the casing.

18 represents the steam-inlet pipe, which passes through the head of the casing into an elongated steam-chamber 19, which is curved to conform to the path of the vanes as they travel around within the casing. There are preferably provided eight of the vanes 15, spaced apart at angles of forty-ve degrees, and as the steam-chamber also covers about forty-five degrees in arc it follows that the steam is operating on two vanes for almost all of the time, the only exception being at the time when the ends of vanes are passing the ends of the steam-chamber, in which case the steam is operating only upon the first vane; but as soon as said yvane has passed said end then the succeeding vane also passes the rear end of the steam-chamber, and the steam enters behind said succeeding vane and operates upon it likewise. After the vanes have revolved through a little more than ninety degrees from the time when steam passes behind them, the steam-space widens so that the outer edge of the vane passes away from the surface of the casing, allowing the steam to escape over said edge into the exhaust-chamber 20, the steam then passing throu h an exhaust-port 21. It will be understoo that the construction of the steam-ports is identical end for end, so that by admitting steam at one end or the other, as may be desired, the engine may be driven in either direction accordingly.

In order to vallow of the escape of any eX- cess of steam or water condensed therefrom, which might be carried over by the vanes as they complete their revolution, there is connected with each steam-inlet pipe a pipe 22, leading to the exhaust-chamber 20 of the cylinder and closed by a valve 24. If the steam is admitted at one end, the valve leading to this drain-pipe is open at the opposite end, and vice versa.

It will be understood that the drum 16 in the upper chamber of the casing revolves very close to the surface of the casing, so that no steam can escape around the same, and

the result is that there is a forward pressure of the steam upon the vane or piston which is not neutralized by any back pressure upon the revolving cylinder. In order to reduce this back pressure as much as possible, the

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vanes and the grooves into which they enter at the plane of contact of the drums are arranged upon the surfaces of the drums at an angle of about twenty-five degrees with a line thereon parallel with the shafts. In consequence at no time is the whole of the surface of the vane exposed to the back pressure, in fact, only a small portion thereof at any time. As the vane passes the plane through the shafts and comes in front of said plane, there is back pressure upon the portion of the vane which has passed the pla-ne, but on account of this slope to the line parallel with the axis this is only a small fraction of the length of the vane and before the vane has traveled far the steam-chamber extending behind the vane admits steam into the rear thereof and neutralizes the back pressure, or, in other words, provides an impelling force behind the vane. Thus by reason of the inclination of these vanes and grooves there is practically no back pressure of the steam.

In order to permit of the escape of any water which is condensed in the upper drum, there are provided drain-pipes 30, passing through the casing opposite to the open portions of the ends of the drum, which pipes connect with pipes 22, which lead to the exhaust-chamber of the engine. For a similar reason the inner surface of the casing-head, against which the end of the lower drum abuts, is cut away opposite to the lower portion of the drum, as shown at 3l, to permit any water of condensation to drain therefrom.

I claim- 1. In a rotary engine, the combination of a main driving-shaft, a drum thereon, a second shaft, and a second drum thereon contacting with the first drum, a casing surrounding said drums, one of the drums having formed or secured thereon vanes, and the other drum having formed therein grooves into which said vanes enter on the plane where the drums contact with each other, the vanes and grooves being arranged upon the surfaces of the respective drums at an angle with lines thereon parallel with the shafts, the casing fitting closely around the drum having the grooves and also fitting closely around the outer edges of the vanes, means for admitting steam into the space between the drum carrying the vanes, and the casing around the vanes at a point adjacent to the plane of contact between the two drums, and means for exhausting the steam at a point of the casing remote from said plane of contact, substantially as described.

2. In a rotary engine, the combination of a main driving-shaft, a drum thereon, a second shaft, and a second drum thereon contacting with the first drum, a casing surrounding said drums, one of the drums having formed or secured thereon vanes, and the other drum having formed therein grooves into which said vanes enter on the plane where the drums contact with each other, the grooves being substantially V-shaped in cross-section and the vanes corresponding therewith in crosssection but tapering more sharply than the grooves, the vanes and grooves being arranged on the surfaces of the respective drums at an angle with lines thereon parallel with the shafts, the casing fitting closely around the drum having the grooves and also fitting closely around the outer edges of the vanes, means for admitting steam into the space between the drum carrying the vanes, and the casing around the vanes at a point adjacent to the plane of contact between the two drums, and means for exhausting the steam at a point of the casing remote from said plane of contact, substantially as described.

3. In a rotary engine, the combination of a main driving-shaft, a drum thereon, a second shaft, and a second drum thereon contacting with the first drum, a casing surrounding said drums, one of the drums having formed or secured thereon vanes, and the other drum having formed therein grooves into which said vanes enter on the plane where the drums contact with each other, the casing fitting closely around the drum having the grooves and also fitting closely around the outer edges of the vanes, means for admitting steam into the space between the drum carrying the vanes, and the casing around the vanes at a point adjacent to the plane of contact between the two drums, the steamchamber to which the steam is admitted to pass into said space being curved to conform to the path of the vanes and extending substantially over the space between, and occupied by, two adjacent vanes, and means for exhausting the steam at a point of the casing remote from said plane of contact, substantially as described.

4. In a rotary engine, the combination of a main driving-shaft, a drum thereon, a second shaft, and a second drum thereon contacting with the first drum, a casing surrounding said drums, one of the drums having formed or secured thereon vanes, and the other drum having formed therein grooves into which said vanes enter on the plane where the drums contact with each other, the vanes and groove being arranged on the surfaces of the respective drums at an angle with lines thereon parallel with the shafts, the casing fitting closely TOO IIO

around the drum having the grooves and also in either direction as may be desired, and means for exhausting the steam at a point of the casing remote from said plane of Contact, substantially as described.

5. In a rotary engine, the combination of a maindriving-shaft, a drum thereon, a second shaft, and a second drum thereon contacting with the first drum, a casing surrounding said drums, one of the drums having formed or secured thereon vanes, and the other drum having formed therein grooves into which said vanes enter on the plane where the drums Contact with eachl other, the casing fitting closely around the drum having the grooves and also fitting closely around the outer edges of the vanes, means for admitting steam into the space between the drum carrying the vanes, and the casing around the vanes at a point adjacent to the plane ofcontact between the two drums, means for exhausting the steam at a point of the casing remote from said plane of contact, and a suitably-controlled drain-pipe connected with each steam-inlet pipe and adapted to be used in conjunction with the steam-inlet pipe at the opposite end, substantially as described.

6. In a rotary engine, the combination of a main driving-shaft, a drum thereon, a secondshaft, and a second drum thereon contacting with the first drum, a casing surrounding said drums, one of the drums having formed or securedthereon vanes, and the other drum having formed therein grooves into which said vanes enter on the plane where the drums contact with each other, the casing fitting closely around the drum having the grooves and also fitting closely around the outer edges of the vanes, the inner end of the casing-head against which the vane-carrying drum abuts being cut away opposite to the lower portion of the drum to permit the water of condensation to drain therefrom, means for admitting steam into the space between the drum carrying the vanes, and the casing around the vanes at a point adj aoent to the plane of contact between the two drums, and means for exhausting the steam at a point of the casing remote from said plane of contact, substantially as described.

7. In a rotary engine, the combination of a main driving-shaft, a drum thereon, a second shaft, and a second drum thereon contacting with the first drum, a casing surrounding said drums, one of the drums having formed or secured thereon vanes, and the other drum having formed therein grooves into which said vanes enter on the plane where the drums contact with each other, the casing fitting closely around the drum having the grooves and also fitting closely around the outer edge of the vanes, a steam-inlet pipe at each end of the engine for admitting steam into the space between the drum carrying the vanes and the casing around the vanes at a point adjacent to the plane of contact between the two drums7 means for exhausting the steam at a point of the casing remote from said plane of contact, means for controlling the passage of steam through each steam-pipe, and a pipe at each end of the engine leading from eaoh steam-inlet pipe between the valve `and the cylinder, and a valve controlling each of said latter pipes, whereby when steam is admitted at either end the exhaust trapped steam may be released at the opposite end, substantially as described.

In witness whereof I have hereunto set my hand in the presence of two subscribing witnesses.

H. E. THOMAS.

Witnesses E. WooDwARD, Bnssrn GORFINKEL. 

